reactos/drivers/parallel/parport/hardware.h

41 lines
1.4 KiB
C

/*
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: Parallel Port Function Driver
* FILE: drivers/parallel/parport/hardware.h
* PURPOSE: Hardware definitions
*/
#ifndef _HARDWARE_H_
#define _HARDWARE_H_
/*
* The following constants describe the various signals of the printer port
* hardware. Note that the hardware inverts some signals and that some
* signals are active low. An example is LP_STROBE, which must be programmed
* with 1 for being active and 0 for being inactive, because the strobe signal
* gets inverted, but it is also active low.
*/
/*
* bit defines for 8255 status port
* base + 1
* accessed with LP_S(minor), which gets the byte...
*/
#define LP_PBUSY 0x80 /* inverted input, active high */
#define LP_PACK 0x40 /* unchanged input, active low */
#define LP_POUTPA 0x20 /* unchanged input, active high */
#define LP_PSELECD 0x10 /* unchanged input, active high */
#define LP_PERRORP 0x08 /* unchanged input, active low */
/*
* defines for 8255 control port
* base + 2
* accessed with LP_C(minor)
*/
#define LP_PINTEN 0x10
#define LP_PSELECP 0x08 /* inverted output, active low */
#define LP_PINITP 0x04 /* unchanged output, active low */
#define LP_PAUTOLF 0x02 /* inverted output, active low */
#define LP_PSTROBE 0x01 /* inverted output, active low */
#endif /* _HARDWARE_H_ */